At least 54 children and about 30 adults swam from Morocco to Spain's North African enclave of Ceuta in rough seas and fog, Spanish television reported on Saturday.

Video footage on Spanish television channel RTVE showed the Civil Guard launches making repeated rescue attempts to bring some of the swimmers to safety, while others swam across to the enclave.

The children, who were mostly Moroccan, were taken to temporary centres in Ceuta, where authorities called for help from the central government in dealing with the latest arrivals.

"Don't leave us alone. This is a matter of state. This has to be resolved," Juan Rivas of the Ceuta regional government told reporters on Saturday.

On August 26 last year, hundreds of migrants took advantage of a thick mist to swim to Ceuta from neighbouring Morocco, local police said. In 2021, one boy was seen floating on empty plastic bottles in his attempt to reach Ceuta.

Spain's two enclaves on Morocco's Mediterranean coast, Ceuta and Melilla, share the European Union's only land borders with Africa. The enclaves sporadically experience waves of attempted crossings by migrants trying to reach Europe.

Moroccan nationals detained during the crossings are immediately sent back to Morocco unless they are underage or seeking asylum.

People from other nationalities are taken to special centres where they are given shelter and released after a few days.

Three years ago, at least 23 people died in a stampede when about 2,000 migrants tried to storm into Melilla, pushing down the border fence.